can someone please help?

Question

2 Cu + S  →  Cu2S

When 98.6 g of copper reacts with 41.2 grams of sulfur 

1. What is the % yield if 96.2 grams of product are formed?

Answer 1

2 Cu + S  →  Cu₂S

1). Find the limiting reactant:

mols Cu present = 98.6 g Cu x 1 mol Cu / 63.5 g = 1.55 mols Cu

mols S present = 41.2 g S x 1 mol S / 32 g = 1.29 mols S

Based on the mol ratio for Cu:S of 2:1, Cu is the limiting reactant.

2). Based on the mols of the limiting reactant, determine the theoretical yield of Cu₂S

Theoretical yield = 1.55 mols Cu x 1 mol Cu₂S / 2 mols Cu x 159 g Cu₂S / mol = 123 g Cu₂S

3). Calculate % yield:

% yield = actual yield / theoretical yield (x100%) = 96.2 g / 123 g (x100%) = 78.2% yield